1. Field of Invention
The invention relates to a full color display panel with a mirror function and, in particular, to a full color display panel with a mirror function that has a semi-reflecting layer.
2. Related Art
The colorizing technologies utilized in the present organic electroluminescent displays mainly include the following three. The first technology is “Three Primary Colors Light-emitting Method” that uses respectively three primary colors (Red, Green, and Blue) for an independent electroluminescent unit. The second technology is “Color Conversion Medium” that includes a blue light material and cooperates with a red organic fluorescent material and a green organic fluorescent material to generate various colors. The third technology is “Color Filter Method” that includes white light electroluminescent layer and color filters. Hereinafter, the color conversion medium technology is taken for an example and is described below.
Idemitsu Kosan Co. is one of the leaders in developing the color conversion medium technology. As shown in FIG. 1, a full color display panel 3 comprises an organic light-emitting area 31, a planarization layer 32, a color conversion layer 33, a glass substrate 34 and an encapsulating cap 35. The organic light-emitting area 31 is disposed on the planarization layer 32, the planarization layer 32 is disposed on the color conversion layer 33, the color conversion layer 33 is disposed on the glass substrate 34, and the encapsulating cap 35 is connected to the glass substrate 34. In this case, the organic light-emitting area 31 includes a first electrode 311, an organic functional layer 312 and the second electrode 313, which are disposed on the planarization layer 32 in sequence. The organic functional layer 312 is made of a blue light material, so that the organic light-emitting area 31 can emit blue light. The color conversion layer 33 comprises a plurality of blue filters 331, green filters 332, red filters 333, green conversion films 332′, and red conversion films 333′. The green conversion films 332′ and the red conversion films 333′ are disposed on the green filters 332 and the red filters 333, respectively. The filters 331, 332, and 333 are respectively corresponding to the pixels of the organic light-emitting area 31.
The blue light emitted from the organic light-emitting area 31 may pass through the green conversion film 332′ and red conversion film 333′, and is respectively converted into green light and red light. The green light and red light converted from the blue light pass the green filter 332 and the red filter 333 respectively, to increase the contrast of the green light and the red light. At the meanwhile, the blue light emitted from the organic light-emitting area 31 also passes through the blue filter 331. Finally, a driving circuit is provided to produce the desired color screen according to the generated three primary colors (red light (R), green light (G), and blue light (B)).
In the conventional color display panel 3, however, since at least three photolithography processes are necessary to form the green conversion films 332′ and the red conversion films 333′ on the green filters 332 and the red filters 333, the manufacturing processes of the color display panel 3 are more complex and the cost thereof is increased. Furthermore, since the color display panel 3 includes the planarization layer 32 to make the whole panel more planar, the thickness of the whole panel 3 is also increased, which did not follow the trend toward lightweight and compact devices.
In addition, from the pragmatic point of view, the applications of the full color display panel can be further expanded if it has a reflecting mirror function. To achieve such an effect, a conventional art is to attach a reflecting film onto a surface of the display panel. Thus, the display panel renders dual functions of displaying images and reflecting images.
However, since the reflectance of the reflecting film is inversely proportional to its transmittance (i.e. the better its reflectance is, the worse its transmittance is), those display panel attached with reflecting films generally have decreased brightness. Moreover, since the reflecting film is attached onto the display panel with an adhesive, which has limited lifetime, the attached reflecting film is not ideal for long-term usages.
It is therefore a target to provide a full color display panel to solve the above-mentioned problems.